Fuel-injection system



Patented Apr. 3, 1928.

UNITED STATES LOUIS O. FRENCH, 0F MILWAUKEE, WISCONSIN.

F UEL-INJ ECTION SYSTEM.

ses@ @e Application tiled February 15, 1926. Serial No. 88,406.

The invention relates to fuel injection systems.

ln electrically-controlled fuel-feeding` or injection systems where the passage of fuel to the engine cylinder is controlled directly or indirectly by an electroniagneticaliypperated fuel-metering device, it has heretofore been proposed to vary the amount of fuel furnished the engine by varying the period ot' cnergization of the metering control electromagnet, and whilcl find that with suitl able .switch mechanism this may be carried out, l have dis"overed that a far more sensitive regulation of the amount of fue] may he ctlected by varying the strength ol' the current supplied to the metering control electromagnet and thus vary the extent of movement of the fuel-metering device and the object of this invention is to provide a fuel feeding or injection system for etiecting this result.

A further object of this invention is to provide a control :mechanism for the control circuit for the electromagnctically-operatcd fuel-metering device wherein the period of encrgization of the control magnet may be substantially constant for varying speeds of the engine and the amount of fuel controlled h v a variable resistance in said circuit which may he automatically varied by a speed-responsive device associated with the engine.

further object of the invention is to provide a control mechanism for the control circuit for the electromagnctically-operated fuel-metering device wherein both the period ot energization and the extent of this energizatiou may be varied so as to control the time the metering device is rendered operative and the extent of movement of said device. and, further. to associate these controls together so as to secure efficient regulation of the fuel supply to the engine.

The invention further consists in the several features hereinafter set forth and mor(I particularly defined by claims at the conclusion hereof.

ln the drawing,y Fig. l is a semi-diagrammatic view ot' a fuel injection system embodying the invention;

Fig. 2 is a vertical sectional view through a control me'hunism embodying the invention:

Fig. 3 is a vertical sectional View through another control mechanism embodying the invention.

Referring to Fig. 1, the fuel injection system instanced here includes a fuel supply tank 4 connected by a pipe 5 with a. fuel pump 6, of any suitable construction, which is generally driven by the engine and is adapted to supply fuel to a pressure supply pipe 7, and is preferably of a, t e to insure a relatively constant Supply o fuel to said pipe 7 in which the fuel is maintained, while the pump is operating, at substantially constant pressure by means of a pressure valve mec anism of any suitable construction. As shown, pressure valve mechanism 8 includes a casing made up of parts 9 and 10 with 'a diaphragm 11 secured between them, a valve 12 working in a, slotted guide tube 13 and being normally urged by a spring 14, acting on the dia,- phragm to close o communication between a small passage 7 communicating with the pressure pipe 7 and the chamber 15 which communicates with a pipe 16 that returns the excess fuel to the tank 4, the tension of the spring; 14 being adjusted by means of a slide block 17 associated with a bolt 18 in threaded engagement with the part of the casing. From the pi e 7 branch pipes i9 (only one being shown? respectively lead to the engine cylinders. An electromagnetically-operated meterin device instanced here as a control valve dev1ce 20, which may he the fuel injector valve or which may be associated with a fuel-pressure-operated injector valve. as shown in my copending application. Serial No. 66,769, filed November Al, 1925. controls the supply of fuel from the pipe 19 to the cylinder of the engine with which said pipe is associated. This control 'alve device includes a control valve 21 having an armature 22 associated with an electromagnet 23 and controlling passage of fuel from its supply pipe 19 through the valve casing `and a passage, here shown as the fuel nozzle 24, into the cylinder of the engine in the head 25 of which the device is mounted, a spring 26 normally tending to close the valve which is opened by the olectromagnet attracting the armature 22 when the same is energized. The electro-` magnetic valve herein shown is more particularly described in the aforementioned a plication, but as any suitable construction o electromagnet valve may be used in the system further description thereof is deemed unnecessary.

The metering control electromagnet 23 receives its current from a battery 27, or other suitable source of current supply, through a control circuit including a control switch mechanism 28. This control switch mechanism may be of any suitable construction and is here shown as including a rotatably adjustable case 29 carrying a suitably insulated fixed Contact 30, a pivoted contact 31 urged by a spring 32 against a cam 33 mounted on a. shaft 33 driven by the engine, said cam permitting the contacts and 31 to be engaged for a certain cyclic period and thereafter moving said contact i 31 out of engagement with the contact 30,

the timing of -the circuit-closin period bein determined by the angular a justmcnt of tige case 29 relative to said cam.

The control circuit also includes a variable resistance device 34, here shown as including the resistance 35, and a pivoted switch arm 36 which may be operated in any suitable manner. As shown, this switch arm is arranged for manual operation, either by hand or oot, by connection with a suitably insulated rod or plunger 37 having a button 38 associated with a spring 39 normally acting to move the arm 36 so as to include the entire resistance 34 and which rod, upon the operation by the operator, moves the switch arm 36 to gradually cut out sections of the resistance 35.

A conductor 40 connects one side of the battery with the arm 36, and a conductor 41 connects the resistance with one terminal of the energizing coil of the electroma et, while the other terminal of said coll is grounded at 42. A conductor 43 connects the other side of the batter with the insulated switch contact 30 wh e the other contact is grounded as at 31. Acondenser 44 may be connected across the contacts to reduce arcing.

With this construction the umping system supplies the pipe 19 nit fuel under pressure and the amount of this fuel passing to the engine is under the control of the metering valve 21 which in turn is controlled by the electromagnet. The electromagnet is energized when the contacts 30 and 31 are engaged and under these conditions current from the battery asses through the resistance 35 to the coi of the magnet, and the amount of this resistance is varied by changing the position of the arm 36 so as to include more resistance in the control circuit or reduce the resistance. This varies the strength of the current supplied to the `electromagnet and this, in turn, varies its energizing etlect so that with more resistance in the circuit the control valve will be lifted through a less distance when the electromagnet is energiaed than when a greater current with less resistance is allowed to flow through said electromagnet, with the-result that theflift of the I find that this produces a more sensitive t control of the metering valve than could be possible mechanically, and that very small quantities of fuel may be handled so that thc system may be used elfectivel Aon the relatively small bore engines of t e automotive type. As shown, the cam 32 being one having an unvarying relief surface, an increase in engine speed will cut down the eriod ofd energization of the magnet, but this may be compensated for by cutting out some of the resistance. Furthermore, excluding the resistance while the engine is running at any given speed will produce an increased charge of fuel and cause the engine to accelerate. lVhere the engine is used as the propel `111g motor of a. vehicle the depression of the plunger 37Y will act to accelerate the engines speed and may in such an association be operated by the foot of the operator.

In Fig. 2 I have shown a form of control mechanism in which a cam 45 is used in place of the cam 32 and is sldably mounted on an engine-driven shaft 45. This cam has relief portions 46 which are tapered or so designed as to permit a substantially constant circuit-closing eriod of the contacts 30 and 31 (shown in fill] in Fig. 1) throughout a predetermined speed range, and a variable resistance 47, here shown of the `carbon pile type, is under the control of a speedresponsive device. As here shown, this device includes a spider 47 fixed tod the shaft 45 and provided with a bore 47 in which a sleeve 48 is free to move within the limits determined by a longitudinal slot 49 in said sleeve, and a pin 50 in the hub of the spider` and the oppositely disposed arms of said ider have levers 51 pivotally mounted t ereon, their forked ends 52 being provided with pins 53 mounted in an annular groove 54 formed in the upper part of said sleeve, their outer ends carrying the weights 55. A spring 56, acting in opposition to the governor weights, is interposed between "the upper end of the sleeve 48 and a manuallycontrolled collar 57 slidably mounted on the shaft 44. The collar is moved manually by a lever 58 pivotally mounted on the casing and having forked ends 59 provided with pin projections engaging in the groove of said collar, and an exterlorly disposed operating lou arm. The shaft is suitably journalled in bearings and 6l. The casing 29 is mounted in the main casing so as to be relatively adjustable and has a hand lever 29 for this purpose.

The shaft 45' has a kcyway GEZ therein and a key 63, slidably mounted in said ketvnvay, is connected at its lower end with said sleeve 48 and at tsupper end with said cam 45.

The sleeve 4S has an annular groove t-t therein and a forked lever has pin projections engaging insaid groove and is suitably pivoted at 66. The other end of this lever engages in the groove of an insulated head 67 on a plunger 67' of the carbon pile rheostat 47 so that as the speed of the engine increases the plunger 67 is moved outwardly, thereby decreasing the pressure bctween the carbon disks of said rhcostat and thus increasing the resistance in the control circuit, a spring 68 bearing on said head 67 normally acting to move said plunger i11- wardly to put pressure on the carbon disks to decrease the resistance. \As the construction of a carbon pi rheostat is well known, a detailed showing of the disks is not considered necessary.

As the resistance is increased the strength of the magnetic force will` be decreased, as in the first described construction so that the amount of fuel will be decreased, but since the governo\r also acts on the cam 15 the period of ehergization will not be val'ied substantially for predetermined speed ranges. Thus, the resistance control acts to control the supply of fuel to the engine at different speeds by varying the lift of the valve, and it will be apparent that the plunger 07 may be manually operated and the governor then only *insure a substantially constant period of energization. Furthermore, the movement of the collar 57 by the operator varies the tension of the spring 5G so that the governor may operate through diticrcnt speed ranges to control the amount of resistance included in the control circuit and thus control thelamonnt of fuel supplied to the engine.

In case of a multiclvlinder engine there are as man v reliefs 40 on the cam 15 as there are engine cylinders and the current is distributed in desired cyclic sequence to the branch circuits connected with the electromagnets ot' thc control valves by a spring-pressed brush 69 running over a commutator track 70 including spaced contacts 71 mounted in a removable head 72 of insulating material. said brush receiving current from a springpressed brush 73 carried b v said head and bearing upon a conductor 74 carried by the rotary distributor head 75 of insulating material mounted on the shaft -15 and in which the brush (it) is mounted.

In the construction shown in Fig. 3 a cam 76 cooperating with the movable Contact 31 is slidably mounted on the shaft 77, with which it rotates, and has tapered relief portions 7 8 to vary the relative periods of time that the contacts 31 and 30 (shown in plan in Fig. 1) are engaged on the shifting of said cam longitudinally of said shaft, this longitudinal movement being,lr effected by a key 79 working in a key-way in said shaft and connecting said cam with atcollar 80 havin an annular groove receitving the pin projections on the forked arms of a manually-operated lever 81 pivotally supported on -the switch casing and having an exterio. ly disposed op erating arm 89.

A sleeve 83 is slidably keyed to the shaft 77 and moved longitudinally relative thereto by a governor, including the weighted levers 84 pivotally mounted on the arms of a spider 85 whose hub 86 is secured by screws 87 to an engine-driven shaft 88. The forked arms 89 of said levers 84 have pin projections engaging in an annular groove 90 of said col lar, whereby to move said sleeve 83 upwardly upon an increase of speed. The sleeve 83 has oppositely disposed slots 91 of varying angularity formed therein. Pins 92 carried by -the hub 80 work in said slots and form a driving connection between the shafts 77 and 88. These angular inclined slots 91 colopcrate with said pins 92 and canse a relative angular movement between the hub 86 and sleeve 83, and hence between the shafts 77 and 88 on the longitudinal movement of said sleeve under the action of the governor, and thus cause an automatic changing of the timing of the injection period as the speed 0f -the engine varies. Thls automatic change of timing may, of course, be used in the constructions with the cams shown in Figs. 1 and 2. The shaft 77 is journalled in a bearing 93 and has a shoulder 94 engaging the inner bearing race to prevent its up ard longitudinal movement, and a roller-thrustbearing 95 in interposed between the shafts 77 and 88.

The sleeve 83 also has a' gl'ooved collar position 90 operatively associated with the forked ends of a lever 97, with its pivot` shaft 98 suitably journalled in the switch casing. This shaft carries a segmental gear 90 meshing with a gear 100 on a shaft 1 01 journalled in said casing. A disk 102 of insulating material is mounted on Said shaft 101 and has a current collector ring 103 mounted thereon and conductively connected to a switch arm 104 secured to said disk. A brush 105 bears on the ring 103 and is connected to conductor 40. The arm 1011 engages a resistance wire 106 spirally wound on a Isupport 109 of insulating material supported on the casing and connected at terlninal 108 with the conductor 41. A spring 80. interposed between the sleeve 83 and the collar 80, acts in opposition to the governor weights.

lltl

Au extcriorly disposed manually-operated arm 109 is connected to the .shaft 98 so that Isaid lever may be operated independently of the governor, if desired.

A piu l1() iu the casingr acts as a stop to limit the downward movement of the lever 81 and hence the calu TG.

ln the last-described construction movementy of the cam 76 relative to the contact 8i varies the relative duration of energization period of the electromagnet, and longitudinal movement of the sleeve 83 under the action of the governor lever 89 swings the lever 97 about its pivot 98 and through the gears 99 and 10() turns the shaft lOl and hence swings the switch arm lOl, which cuts iu or out certain sections of the resistance 10G and thus varies the resistance in the control circuit, for the reasons pointed o ut in the first-described construction. Furthermore, movement of the collar 8() varies the tension of the spring 80 to vary the section of the governor and thus accommodate for different speed ran es while varying the position of the cam i6, or the operation of the lever 109 varies the speed range of the governor independent of the position of the collar 80 and hence the cam 7G. Thus both the period of encrgization and the amount of electrical energy furnished the magnet may be varied independently or together to vary the relative period of time the control valve is held open and the lift of the valve durin this period, and hence the amount of fue supplied to the engine. lVith this construction the positioning of the cam 76 in different positions relative to the switch 31 may be used as a general regulator of the fuel supply to the engine to accommodate the load or speed, and the governor-controlled variable resistance under these conditions keeps the amount of the fuel within close limits at the desired load or speed, and the adjustment provided also provides for operation through varying speed ranges.

It will also be understood that the cam 76 may be used in place of the cam in the construction shown in Fig. 2, so that the speed-responsive device acts to control both the duration of cnergization of the magnet through the action of the cam and the strength of cnergization through the action of the rheostat, and that in this instance the rheostat serves as a more delicate control of the fuel supply under the action of the `governor than the use of the cam 76 alone.

lVhile thc` invention has been described more particulal'l in connection with an elect romagnet ieallIy-controlled fuel-metering valve. it will be understood that in a broad scuse any other lsuitable metering device may be associated with the electromagnet, in combination with the control means above described, hence the invention is not to be limited, unless otherwise specified, to the association of control means with a metering valve.

I desire it to be understood that this invention is not to be limited to any particular form or arrangement of parts except in so far as such limitations are specied in the claims or necessitated by the prior art.

lVhat I claim as my invention is:

l. In a fuel su ply system, the combination with a fuel) metering device, of an elcctromagnet for controlling said device, a control circuit for said electromagnet includingr engine-controlled switch mechanism for controlling said electromagnet, and a variable resistance for varying the current supplied to said electromagnet and'thus vary the action of said device and consequently' the amount of fuel furnished the engine.

2. ln a fuel supply system, the combination with a fuel metering device, of an electromagnet for controlling said device, a control circuit for said electromagnet, enginecontrolled switch mechanism for controlling said electromagnet, a rheostat for varying the current supplied to said electromagnetand thus vary the action of said device and consequently the amount of fuel furnished the engine, and an engine-operated speedresponsive device associated with said rheostat to control its operation.

3. In a fuel supply system, the combination with a fuel metering device, of an electro- Inagnet for controlling said device, a control circuit for said electroinagnet including engine-controlled switch mechanism, a variable resistance for varying the current supplied to said electromagnet and thus vary the action of said device and consequently the amount of fuel furnished the engine, and overnorcontrolled means for varying the time of operation of said switch mechanism.

4. In a fuel supply system, the combination with a fuel metering device, of an electromagnet for controlling said device` a coutrol circuit for said electromagnet including,r means for varying the duration and strength of energization of said electromagnet and thus vary the duration of time the device is operated and the extent of movement of said device to thereby control the amount of fuel supplied to the engine.

5. In a fuel supply system, thc combination with a fuel metering device, of an electroma et for controlling the operation of said devlce, a control circuit for said electro magnet including means for varying the duration of energization of said electromagnet, and means for varying the amount of current supplied to said electroniagnet, and an engine-operated speedresponsive device associated with said last-named means to control its operation.

6. In a fuel supply system, the combination with a fuel metering device, of an elecllU tromagnet for controlling the operation of said device, a control circuit for said electromagnet including means for varyin the duration and strength of energization o said clcctromagnet and thus vary the operation olf' said device to control the amount of fuel supplied lo the engine, and an engine-operated speed-responsive device for controlling said means.

T. In u, fuel supply system, the combination with a fuel metering device, of an electromaguet for controlling the operation of said device, a control circuit for said electromagnet including switch mechanism controlling the energizaton period of said electromagnet, a rlieostat controlling the strength of current supplied to said electromagnet, and means for independently varying the action of said switch mechanism and said rheostat.

8. In a fuel supply system, the combination with a fuel metering device, of an electrolnagnet for controlling the operation of said device, a control circuit for said electromagnet includingr engine operated switch mechanism establishing current iiow thereto for a substantially constant period for a predetermined speed range, and a govcrnor-controlled rheostat for varying the current supplied to said electromagnet and thus vary the action of said device and consequently the amount of fuel delivered to the engine.

9. In a fuel supply system, the combination with a fuel metering device, ot' an electromagnet for controlling the operation of said device, a governor, a control circuit for said electromagnet including switch mechanism for varying the relative period of energization of said electlomagnet, a governorcontrolled rheostat for varying the strength of energization of Said electromagnet, and means associated with said switch mechanism for varying the speed range of said governor as the period of energization of said electromagnet is varied by said switch mechanism.

10. In a. fuel supply system, the combination with a fuel metering device, of an electromagnet for controlling the operation of said device, a governor, a control circuit for said electromagnet including switch mechanism for varyin the relative period of ener gization of sai electromagnet, a rheostat, means for separately adjusting said switch mechanism and said rheostat, and governorcontrolled means also `operable to adjust said rheostat, said means cooperating to vary the amount of fuel furnished the engine.

11. In a fuel supply system, the combination with a fuel-metering control electromagnet, of means including a variable resistance for controlling the action of said electromagnet.

12. In a fuel supply system, the combination with a fuel-metering valve, of an electromagnet controlling said valve, and means controlling the operation of said electromagnet including a variable resistance for varying the current supplied to said electromagnet and thus var the lift of said valve and consequently tlie amount of fuel furnished the engine.

13. In a fuel supply system, the combination with a fuel-metering valve, of an electromagnet for controlling said valve, a control circuit for said electromagnet including engine-controlled circuit control mechanism for controlling said electromagnet, and a variable resistance for varying the current Supplied to said electromagnet and thus vary the lift of said valve and consequently the amount of fuel furnished the engine.

14. In a fuel supply system, the combination with a fuel-metering valve, of an electromagnet for controlling said valve, a control circuit for said electromagnet including engine-controlled circuit control mechanism for controlling said electronnignet, and an engine-controlled variable resistance for varying the current supplied to said electromagnet and thus vary the lift of said valve and consequently the amount of fuel furnished the engine.

In testimony whereof, I affix my signature.

LOUIS O. FRENCH.

CERTIFICATE OF CORRECTION.

Patent No. 1,664, 614.

Granted April 3, 1928, to

LOUIS O. FRENCH.

lt is hereby certified that error appears in the printed specification of the above numbered patent requii'ing correction as follows:

word "section" read "action"; and that the said Letters Patent should be read with this correction therein that the seme may conform to the record of the ene in the Patent Office.

Signed and sealed this 20th day of November. A. D. 1928.

(Seal) M. J. Moore,

Acting Commissioner of Patente.

Page 4, line 22, for the tromagnet for controlling the operation of said device, a control circuit for said electromagnet including means for varyin the duration and strength of energization o said clcctromagnet and thus vary the operation olf' said device to control the amount of fuel supplied lo the engine, and an engine-operated speed-responsive device for controlling said means.

T. In u, fuel supply system, the combination with a fuel metering device, of an electromaguet for controlling the operation of said device, a control circuit for said electromagnet including switch mechanism controlling the energizaton period of said electromagnet, a rlieostat controlling the strength of current supplied to said electromagnet, and means for independently varying the action of said switch mechanism and said rheostat.

8. In a fuel supply system, the combination with a fuel metering device, of an electrolnagnet for controlling the operation of said device, a control circuit for said electromagnet includingr engine operated switch mechanism establishing current iiow thereto for a substantially constant period for a predetermined speed range, and a govcrnor-controlled rheostat for varying the current supplied to said electromagnet and thus vary the action of said device and consequently the amount of fuel delivered to the engine.

9. In a fuel supply system, the combination with a fuel metering device, ot' an electromagnet for controlling the operation of said device, a governor, a control circuit for said electromagnet including switch mechanism for varying the relative period of energization of said electlomagnet, a governorcontrolled rheostat for varying the strength of energization of Said electromagnet, and means associated with said switch mechanism for varying the speed range of said governor as the period of energization of said electromagnet is varied by said switch mechanism.

10. In a. fuel supply system, the combination with a fuel metering device, of an electromagnet for controlling the operation of said device, a governor, a control circuit for said electromagnet including switch mechanism for varyin the relative period of ener gization of sai electromagnet, a rheostat, means for separately adjusting said switch mechanism and said rheostat, and governorcontrolled means also `operable to adjust said rheostat, said means cooperating to vary the amount of fuel furnished the engine.

11. In a fuel supply system, the combination with a fuel-metering control electromagnet, of means including a variable resistance for controlling the action of said electromagnet.

12. In a fuel supply system, the combination with a fuel-metering valve, of an electromagnet controlling said valve, and means controlling the operation of said electromagnet including a variable resistance for varying the current supplied to said electromagnet and thus var the lift of said valve and consequently tlie amount of fuel furnished the engine.

13. In a fuel supply system, the combination with a fuel-metering valve, of an electromagnet for controlling said valve, a control circuit for said electromagnet including engine-controlled circuit control mechanism for controlling said electromagnet, and a variable resistance for varying the current Supplied to said electromagnet and thus vary the lift of said valve and consequently the amount of fuel furnished the engine.

14. In a fuel supply system, the combination with a fuel-metering valve, of an electromagnet for controlling said valve, a control circuit for said electromagnet including engine-controlled circuit control mechanism for controlling said electronnignet, and an engine-controlled variable resistance for varying the current supplied to said electromagnet and thus vary the lift of said valve and consequently the amount of fuel furnished the engine.

In testimony whereof, I affix my signature.

LOUIS O. FRENCH.

CERTIFICATE OF CORRECTION.

Patent No. 1,664, 614.

Granted April 3, 1928, to

LOUIS O. FRENCH.

lt is hereby certified that error appears in the printed specification of the above numbered patent requii'ing correction as follows:

word "section" read "action"; and that the said Letters Patent should be read with this correction therein that the seme may conform to the record of the ene in the Patent Office.

Signed and sealed this 20th day of November. A. D. 1928.

(Seal) M. J. Moore,

Acting Commissioner of Patente.

Page 4, line 22, for the 

